1. Field of the Invention
The present invention relates to an announcement device in a switching system, and more particularly to an announcement device including a virtual recorder in an electronic switching system.
2. Background of the Related Art
In general, an announcement device is a device for providing announcement services, i.e., recording the contents of voice services provided by a telecommunication service provider, and playing, or announcing the recorded voice data for the subscriber.
Referring to FIG. 1, a related art announcement device 10 includes a switch matching, control section 11 to control announcement functions and record/monitor announcement functions, and a main switch block 20 to send and receive information to/from the announcement device 10. A switch sub-highway (SHW) channel 15 is provided for inputting/outputting frame synchronization signals FS, clock signals CLK, and voice data (Rx Data/Tx Data) to/from the announcement device 10 and the switch 20, in accordance with control signals of the SHW section 11.
FIG. 2 shows input/output structures of voice memory signals within the switch sub-highway section 11 in FIG. 1. Specifically, the signals include an address signal, a data signal, a chip select (CS), a write enable (WE), and an output enable (OE).
FIG. 3 illustrates a series of voice signals, which have been inputted to the SHW section 11 of the announcement device 10. The voice signals are received as serial data, and inputted to a voice memory 11b in the form of parallel voice signals through the series-parallel converting section 11a. The parallel data is then converted to series data by a parallel-series (PS) connecting section 11c. The voice data is then outputted to a switch block 20 through the SHW channel 15.
Additional detail on the series-parallel converting section 11a is shown in FIG. 4, and additional detail of the parallel-series converting section 11c is shown in FIG. 5. With respect to FIG. 4, the series-parallel converter 11a receives the serial voice data signals, along with a clock signal and a clear signal. In response, the series-parallel converter 11a generates parallel voice data. Next, referring to FIG. 5, the parallel-series converter 11c receives parallel voice signals from the voice memory 11b, along with a clock signal and a SH/LO signal, and outputs serial voice data.
An operation of the related art announcement device constructed above will now be described.
The SHW channel 15 typically consists of 64 voice channels. While the number of channels may be variable in each announcement device, an operation with 64 voice channels will be exemplified herein below.
As shown in FIG. 1, the SHW channel 15 comprises a FS, which is a reference clock signal signifying a start of channel xe2x80x9c0xe2x80x9d, and a clock signal CLK providing a time clock for the transmission of voice data, such as Rx Data and Tx data. The FS signal is operated at 8 KHz, while the clock signal CLK is operated at 8 MHz. Therefore, a total of 1,024 clock signal CLK periods exist in a single FS signal period.
The SHW control section 11 controls the FS signals, CLK signals, Rx Data, and Tx Data in the SHW channel 15. Under normal conditions, that is, when the system is not recording, all of the 64 channels are used for announcement services. If, in the normal condition, a request for an announcement is received from a high level processor, the SHW control section 11 loads an announcement message stored in the voice memory on a particular SHW channel among the 64 voice channels of the SHW channel 15.
Here, 16 clock signals CLK comprise one channel or a time slot, and 64 channels exist in a single FS signal. Since the SHW channel 15 is in serial lines, the FS signals and the CLK signals constitute each line to consecutively operate to conform to the FS signals. In other words, as shown in FIG. 6, if voice data synchronized as 16 CLK signals in accordance with the FS signals are outputted to each channel, 64 announcement services can be performed through 64 channels in the 1,024 clock signals.
If an address of a particular channel is latched by the SHW control section 11 in accordance with the FS signals and the CLK signals, the voice memory storing the voice messages outputs voice data in accordance with the address. The outputted parallel voice data is converted to series voice data so as to be outputted as Tx Data through a prescribed channel of the SHW channel 15.
Recorded voice data is stored in the voice memory 11b, which is constructed in parallel FIG. 2). In other words, data in the voice memory 11b comprises 20 address signals (address 0-20), 8 data signals (data 0-7), and control signals chip select (CS), write enable (WE), and output enable (OE).
In general, voice is considered to be a single series of analog signals. An analog voice signal is converted to a digital voice signal by an analog-digital converting circuit (CODEC, not illustrated in the drawings) in a voice terminal. In order to store such digitally converted series of voice data in the voice memory 11b, a parallel conversion is required. To do this, the series-parallel (S/P) converting section 11a converts the serial voice data to parallel voice data for storage in the voice memory 11b. 
By contrast, in order to provide a desired announcement service with the voice data stored in the voice memory 11b, the voice data must be transferred to a switch block 20 via the SHW 15. Since the SHW 15 is configured for serial signals, the stored parallel signal data must first be converted to serial data through the parallel-series converting section 11c (FIG. 3).
The voice data loaded on each channel occupies a prescribed channel of the SHW channel 15, and is outputted to a main switch block 20. An announcement service is thereby provided.
FS signals and clock signals CLK are also required for recording or reproducing announcements by the announcement device using serial voice data inputted/outputted to and from a voice terminal. The FS signals and clock signals CLK of the SHW channel 15 for voice services are used for that purpose.
Referring to FIG. 7, once a recording starts, an address latch signal for selecting a particular address signal of the voice memory 11b is synchronized with the clock signals CLK of the channel 0 memory location. A real address of the voice memory is selected in accordance with the address latch signal. The recorded serial voice data is latched in accordance with each clock signal CLK, and is converted to parallel data. Voice data is outputted in accordance with the data latch signals, thereby storing the voice data in a prescribed address of the voice memory 11b in accordance with the latched address signals. Specifically, the parallel data inputted/outputted to and from the voice memory comprises 8 bit data, consisting of bits D0-D7.
If a series of voice signals are inputted, the series-parallel circuit operates in conformity with a clock signal CLK.
Next, the clock signal CLK is a dually divided signal of the original clock signal to convert 8 MHz to 4 MHz. One channel includes 8 clock signals CLK. In other words, while one channel includes 16 clock signals CLK in the original 8 MHZ, another channel includes 8 clock signals CLK in the divided 4 MHz. Accordingly, D7 is outputted from the first CLK, D6 is outputted from the second CLK, and D0 is outputted from the eighth CLK. The data outputted in conformity with the clock signal CLK are latched and stored in the circuit. Therefore, the data is continuously updated in conformity with the clock signal CLK, and necessary data can be latched and taken at the point of time when D7-D0 are outputted.
The recorded voice can then be played back for monitoring in the same manner as recording. That is, when an address signal is outputted by the address latch signal from the channel 0 memory location in accordance with the FS signals and CLK signals, the voice data of the voice memory 11b is synchronized with the CLK signal of channel 0, and outputted as serial voice data through the voice terminal, thereby enabling monitoring.
As described above, the announcement service and the monitoring/recording service share the same function for generation of the particular address and generation of the voice data corresponding to the particular address. However, a functional difference lies in that the announcement service loads the voice data on the Tx Data of the SHW channel 15, while the monitoring service transfers the voice data to the local voice terminal, for example at a front face panel of the announcement device.
Specifically, with reference to FIG. 3, the voice data generated from the voice memory 11b is 8 bit parallel data, and the line sent to the switch through the SHW is a serial data line. Thus, an announcement service can be performed by loading the serial voice data on the corresponding SHW channel 15 by converting the parallel voice data to the serial voice data.
The front face panel, which provides the monitoring function as stated above, refers to a front portion of the announcement device, i.e., a front panel portion seen at the front by a user when a board is mounted therein. The front face panel can thus be manipulated by the user.
If an operator needs to listen to the contents stored in the voice memory 11b, so as to monitor them, the contents can be heard through the front face panel by manipulation thereof, i.e., by connecting a earphone to a jack mounted on the front face panel.
As described above, the parallel data stored in the voice memory 11b is converted to serial data when reproducing the voice data. The converted serial data are digital signals. Since the audible signals through an output are analog signals, however, a digital-analog converting circuit (CODEC; not shown in the drawings) is required. If the digital signals are converted to analog signals by the CODEC, the operator can listen to the voice data through an earphone.
The related art announcement device in an electronic switching system as described above has various problems. For example, when an operator records or reproduces voice data, a particular channel for announcement services is occupied. Therefore, the particular channel cannot be used for announcement services.
In other words, one out of the 64 channels is occupied when recording or monitoring the voice data. Thus, no announcement service can be provided through the occupied channel, and only 63 channels are available for announcement services.
Announcement services are thus interrupted on a particular channel when recording and monitoring the voice data during the announcement. For instance, when recording or monitoring the voice data while an announcement is on channel 0, the announcement is interrupted since channel 0 is occupied for recording and/or monitoring
The above references are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and/or technical background.
It is an object of the present invention to provide an announcement device including a virtual recording section in an electronic switching section which substantially overcomes problems caused by disadvantages in the related art.
Another object of the present invention to provide an announcement device including a virtual recording section in an electronic switching system, which can perform recording/monitoring of voice data simultaneously with announcement services, without occupying a particular channel.
Another object of the present invention to provide an announcement device including a virtual recording section in an electronic switching system, which can perform the announcement services with address latch signals and data latch signals occupying a virtual channel additionally employed.
Another object of the present invention to provide an announcement device including a virtual recording section in an electronic switching system, which can improve the manner of occupying channels so as to record/monitor voice data without occupying a particular channel by using a virtual channel.
To achieve at least the above objects, in whole or in parts, there is provided an announcement device including a virtual recording section comprising a first SHW control section for controlling an announcement, a second SHW control section for controlling the announcement, a SHW channel for passing of control signals from the first and the second SHW control sections, and a switch block for performing an announcement by being connected to the SHW channel.
According to a preferred embodiment of the present invention as broadly described herein, all of the SHW channels can be engaged in announcement services during the recording or reproducing of voice data, and monitoring or a self loop-back test can be performed with respect to the voice recording or announcement without interrupting the announcement services through a particular channel.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objects and advantages of the invention may be realized and attained as particularly pointed out in the appended claims.